GAS Gasmaster, Инструкция по установке, эксплуатации и обслуживанию

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11
Warning
Gas Alarm Systems strongly recommends that remote
inhibit switches be key operated only, and that
access to the key should be restricted to authorised
personnel. A Gasmaster system that has been inhibited
without other safety precautions being in place may
not provide the protection for which it was designed.
Steps should be taken to ensure that all appropriate
personnel are aware when a Gasmaster system is
inhibited.
Remote ACCEPT/RESET
Close the contact momentarily to accept alarms and
cancel audible alarms. Close the contact again when
the hazard is cleared to reset alarms.
Remote INHIBIT
Closing the contact will inhibit alarms on all input
channels. Channels will remain inhibited until the
contact is opened; the Gasmaster will then return
to its original state (any channels that have been
set to inhibit using the Supervisor menu will remain
inhibited). Figure 2.15 shows wiring configurations for
remote inputs.
Gas Alarm Systems recommends screened cables for
connecting remote switches. The screen should be
terminated at the appropriate ‘SCR’ terminal.
2.9 Connecting output devices
WARNING: After accounting for internal power
consumption, the maximum power available for input
and output devices is 48 W
2.9.1. Audible visual alarms
Figure 2.16 shows a typical wiring diagram for audible
& visual (A/V) alarms, in this example a two-tone
sounder is depicted. The A/V drive from Gasmaster is
capable of providing up to 650mA, which equates to
two general purpose A/V alarm devices using xenon
type beacons. A greater number of LED-based beacons
may be powered; contact Gas Alarm Systems for
advice. Gasmaster is compatible with 12 V dc or 24 V dc
A/V alarms: refer to Figure 2.16 for link settings.
Gasmaster is compatible with A/V alarms which require
a common 0V supply (+VE switched), or a common
+VE DC supply (0V or ‘-VE’ switched). Connect the A/V
device to the ‘AV +VE SWITCHING’ or ‘AV -VE SWITCHING’
terminals as appropriate.
Two separate sounder outputs are provided to activate
on level 1 and level 2 alarms respectively (terminal
AV2 becomes active on alarm level 1; AV3 becomes
active on alarm level 2). If a single tone sounder is
used, connections should be to terminal AV2 (and the
common terminal) only. T
erminal AV1 is intended to drive a visual alarm and
activates on a level 1 alarm.
2.9.2. Common relay connections
Double-Pole-Change-Over (DPCO) relays with contact
rating of 250 V ac 8 A (non-inductive), 5 A (inductive)
are provided for Alarm 1, Alarm 2 and Fault. Each relay
can be set in its non-active state as energised (Fail safe)
or de-energised. It is common practice to set the Fault
relay as Fail Safe so in the event of power loss, the fault
relay will change state. See Figure 2.5 for Common
Relay terminal location and Figure 2.17 for contact
definitions. Terminals are fitted adjacent to all relay
blocks to provide 12 V or 24 V dc supplies for switching
low power devices. The dc auxiliary output terminals
may be set to either 12 V dc or 24 V dc by moving the ‘V
AV’ link. Refer to Figure 2.5 on page 7 for details.
2. Installation